How To FIX P0172 OBD-II Code (System Too Rich (Bank 1)

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How To FIX P0172 OBD-II Code?
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P0172 is a trouble-causing issue code that means  “Fuel Tank Extremely Excessive “ The computer that is made in your automobile detects and judges the vehicle’s air-fuel combination has far much excessive fuel, the warning code is then triggered.

Is Code P0172 Dangerous? While operating an automobile with a P0172 defect for an extensive duration might aggravate engine degradation and spark plug malfunctioning.

Meaning Of P0172

P0172 System too rich bank 1 means that the fuel and air mixture which is passing in the combustion chamber of an automobile contains a high amount of fuel which is due to the fault in the injectors of an automobile.

It means that the injectors are providing an excessive amount of fuel to the combustion chamber. The Engine Control Module (ECM) computes the required compensatory damages to compensate for the difference between air-fuel ratios in the combustion chamber.

Meaning Of P0172

If the remuneration is immense the overall air-fuel proportion is too svelte, the ECM interprets the situation as a fuel injection framework mishap and illuminates MIL. Vehicles perform best when the air-fuel proportion ratio is 14.7 air to one part each.

If the amount of air is less then the power train control module (PCM ) attempts to adjust by pushing a mild amount of fuel to level up the ratio of air-fuel proportion.

Importance Of Bank 1 In P0172

The “Bank 1” implies that the fault is targeted on the rear of a vehicle containing only one cylinder. The orthodox four-cylinder engine just has a single bank, that bank is referred to as bank 1. The automatic six-cylinder engine that is linear has two banks.

OBD-II Code P0172: Symptoms, Causes & Diagnose


The high octane fuel mixture enables the engine to use an excessive amount of fuel. The ECM/PCM maintains the fuel system regulated due to extreme efforts, one may not observe any symptom other than MIL. If another component of the vehicle fails, it can cause extreme damage to the engine. Incomplete combustion fuel entering the engine fatigue tubes might cause combustion to ignite, putting your jade engine at hazard.

Consider the following factors to prevent any form of side effects;

  • Inefficient use of fuel
  • The pungent scent of gasoline emanates from the engine bay or within the vehicle
  • Check engine light illuminated
  • Sloth rolls
  • Seizing up or malfunctioning
  • Engine incapacity
  • There is a pause when the vehicle is accelerated


P0172 is triggered by a range of issues. In various terms, checking the crucial components accountable for ensuring perfect proportion of air-fuel ratio is the only option how it’s malfunctioning.

The following are some causes of P0172;

  • Leakage of fuel injector
  • Contaminated Engine oil
  • Blockage of air filtration
  • Injection of fuel increased due to blockage or malfunctioning pressurization controller
  • Blockage of the air valve
  • Swamping in air filter due to any physical damage
  • Malfunctioning in O2 sensor
  • Leakage in the gas tank
  • Sensor related issues
  • Out-dated software
  • Circuit issues

Diagnosis Of P0172

  • Checking the frequency of fuel injectors with loud illumination
  • Monitoring clog in induction unit
  • Examination of O2 sensor and Mass Air Flow Sensor
  • The undertaking of fuel pressure test

Blunders To Be Avoided When Troubleshooting P0172

The mechanic may not examine the radiator pressure sensor and air circulation system. If the radiator thermistor does not deliver the correct indication, the power train ECU might presume it is constantly frigid.

Diagnostic Tools For Code P0172

  • Handbook
  • Pliers/Screwdriver
  • Detector for cleaning Mass Air Flow
  • Measuring cylinder for gasoline

Process For Fixing Code P0172

The code P0172 can be resolved in a variety of techniques depending on specific issues. There is no magic solution to the problem.

Fortunately, there are some DIY remedies for resolving code p0172. Sometimes these remedies work but they are not permanent the solution to a problem so assistance from local mechanic shop to be seeking.

Expert mechanics recommend two DIY remedies while coping with code p0172. I-e ;

Inspection Of Maf Sensor

Inspection Of Maf Sensor

P0172 code could be triggered by the MAF sensor. If you can’t find the MAF sensor, consult your automobile instructions handbook for information. Unscrew the MAF sensor and clean the wind trapped and blockage in the sensor with a sensor cleaner. It is pivotal to cleanse and sanitize the sensor while gripping it upright so that the spraying doesn’t ruin it. (P0441 Obd2 Code).

Now you can reinsert the sensor after it is cleaned and dried. Examine the vehicle to confirm the presence of p0172 code or the issue is resolved therefore for this purpose you need to utilize an OBD-II analyzer to look for fault.

Inspection Of Oxygen Sensor

Another important thing if you have code p0172 is the examination of the oxygen sensor. It is present around the combustion chamber. If you are facing difficulty with its location consult the vehicle instructions handbook for further guidance. Contact your automobile vendor for the replacement of an identical oxygen sensor.

What Should Be Done To Resolve The P0172 Code Error?

  • Replacement of defective propulsion system and fuel controller
  • Replacement of faulty temperature detector
  • Sanitize oxygen sensor
  • Replacement of malfunctioning air purifier
  • Rectifying vacuum leakage

Driving With Code P0172 Error

While operating a vehicle with code p0172 for a long period of time can cause damage to the engine.

Consideration: Checking the functionality and status of coolant temperature sensors and spark plugs is important while coping with code P0172.

Tips For Further Avoiding P0172 Obd-Ii Error

  • Examination of vehicle performance
  • Fuel maintenance
  • Regular oil change and maintenance
  • Consult mechanic for regular maintenance and repairing faults
  • Keep an eye on gasoline mileage